1. Field of the Invention
The present invention relates to a handy terminal for selectively switching an operation mode and a maintenance mode of a wind turbine generator so that each operation predetermined in each mode for a wind turbine generator is performed, respectively, and a wind turbine generator including the handy terminal. In particular, the invention relates to a handy terminal for a wind turbine generator including a tower provided to stand on the ground or on the water, a nacelle supported on the tower to be controlled to rotate in the yaw direction, and a plurality of rotatable blades to be controlled to move their pitch, and a wind turbine generator including the handy terminal. The handy terminal is connectable to the connectors respectively provided on the lower portion of the tower and the nacelle so as to output operating signals for the operation or maintenance of the wind turbine generator.
2. Description of the Related Art
In recent years, the use of a wind turbine generator to generate renewable energy has become popular in view of environmental preservation.
A large size wind turbine generator often adopts the so-called a nacelle type wind turbine generator comprising a rotor head equipped with blades, a nacelle accommodating a drive train and a generator, and a tower supporting the nacelle. The drive train is for transmitting a torque from the rotor head side to the generator side, and usually includes a speed increasing gear so that rotational speed of the rotor head is increased to transmit to the generator. In order to achieve the effective utilization of the wind energy and the stable supply for the commercial line, the wind farm is composed of a plurality of the nacelle type wind turbine generator within a predetermined area. For example, a prior art for maintenance of a plurality of the wind farm is discloses in Japanese Unexamined Patent Application Publication No. 2009-287453 (Patent Publication 1).
In the maintenance of the wind turbine generator, there is a case in which the rotational shaft (and the rotor head coupled to the rotational shaft) is required to rotate.
For example, when greasing the main shaft bearing of the wind turbine generator, it is required to perform such greasing with rotating the rotational shaft slowly in order to supply grease uniformly on the whole bearing. When detaching or attaching the blades, it is required to rotate the rotor head to a position in which the blade to be detached or attached are in the horizontal direction. In the maintenance of some types of wind turbine generator, the rotational shaft is locked by a lock pin to prohibit the rotational shaft from rotating in view of the safety. In such case, it is required to rotate the rotational shaft to a position in which the lock pin can be inserted the hole of the rotational shaft.
One simple and easy manner for rotating the rotational shaft of the wind turbine in such case could be to rotate a brake disk attached to the rotational shaft in the subsequent portion of the speed increasing gear by hand, or to rotate by manually changing the pitch angle of the blades to rotate the rotational shaft utilizing the wind turbine.